Railway spike aligner

ABSTRACT

A mechanism to pick up magnetically permeable spikes from a random supply and position the spikes at a vertical distance below the source of supply in a particularly oriented fashion. The spikes are passed by gravity along a first course that laterally aligns them in vertical position and thence along a second course that orients the head in a predetermined direction to be thereafter delivered for driving or other use. The device is adapted for auxiliary use with existing spike aligning and driving devices.

United States Patent [72] Inventor Frank W.J0hns0n 3,257,962 6/1966 Doorley et al. 104/17 603 Rich Spokane wash 99207 Primary ExaminerArthur L. La Point [2]] Appl. No. 802,960

. Assistant Examiner-Richard Al Bertsch [22] Filed I969 Atlorne -KeithS Ber man 45 Patented June 1,1971 y g [54] RAILWAY SPIKE ALIGNER 7 Cl 10 D F aims rawmg ABSTRACT: A mechanism to pick up magnetically permea- [52] US. Cl 104/17 b Spikes f a random supp|y and position the Spikes at a P Cl 29/26 vertical distance below the source of supply in a particularly [50] Field of Search 104/17, 2; oriented f hi The Spikes are passed by gravity along a fi t 96 course that laterally aligns them in vertical position and 56 R f C1 d thence along a second course that orients the head in a I l e erences e predetermined direction to be thereafter delivered for driving UNITED STATES PATENTS or other use. The device is adapted for auxiliary use with exist- 3, l 20, l 95 2/ l 964 McWilliams lO4/l 7 ing spike aligning'and driving devices.

Patented June 1, 1971 3 Sheets-Sheet 1.

N MNNRGQ Frank W Johnson,

Patented June 1, 1971 I5 Sheets-Shut 2 F/GURE 4 F/GURE 6 N Frank W Johnson,

INVENTOR.

Patnted June 1, 1971 3,581,665

ATTORNEY RAILWAY SPIKE ALIGNER BACKGROUND OF INVENTION Related Applications There are no applications related hereto filed in this or any foreign country at this time.

Field of Invention This invention relates generally to a device for aligning railway spikes, and more particularly to such a device that removes spikes in singulated fashion from a random supply and passes them by gravity through two aligning courses to ultimately present them at a distance vertically below the input with heads particularly oriented.

Description of Prior Art time consuming operation.

Heretofore to alleviate some of the labor involved, various mechanical spike positioning and driving devices have become known and several are in common use in the railroad industry today. Spikes must still, however, be supplied in such devices in proper position for drivingparticularly oriented and supported in some fashion below the hammer, possibly directly in the predrilled holes in the ties. Since the rail spikes are nonsymmetrical, requiring one particular side to face inwardly toward the rail being held thereby, this configuration further complicates spike orientation.

Heretofore various mechanical devices have become known to maintain a plurality of spikes in a magazine of some fashion and present them ready for driving. These known devices, however, because of the nonsymmetrical nature of the rail spike, have required a hand operation either in loading or at some stage during spike transit therethrough to properly align the spikes. Prior art devices similarly have not been able to accept spikes from arandomly distributed supply without some human intervention. The prior art devices similarly have been of a quite complex mechanical nature generally resulting in low reliability with a high probability of fouling in a fashion to require human intervention to refunction.

My invention is distinguished from this art in providing a spike aligning system that accepts spikes from a random stationary supply to thereafter, by passing them with aid of gravity through two aligning courses without any human intervention, present them at a spaced distance below the input in a particularly aligned and vertically oriented fashion. The operation is essentially an untimed one, allowing random acceptance and transit of spikes. The mechanism is most simple of mechanism and operation and therefore quite reliable and free of fouling. The device is adapted for use as an auxiliary structure on various spike aligning and driving devices of present commerce.

SUMMARY OF INVENTION My invention provides an auxiliary substantially peripheral frame surrounding my mechanism and adapted to be mounted upon existing driving or aligning devices. The upper portion of the frame carries two laterally pivotable arms supporting closed circuit magnets that pick up single rail spikes from a horizontally associated supply.

The arms rotate alternately inwardly to a medial downwardly sloping trough in which the spikes are deposited.

They pass downwardly along the bottom of this trough into paired adjacent downwardly sloping courses defined by side rails spaced at a distance to allow the spike shank to fall vertically downward therebetween but yet support the spikes by then larger heads. Passage of the spike through this course laterally aligns it with the rail facing side of the head pointing either forwardly or rearwardly parallel to the course of spike travel. The spikes pass from this first course to the second head aligning course that provides a downwardly sloping, shaking trough wherein the spikes are turned with the larger rail facing side of the head pointing upwardly. Upon exit from the head aligning course, the spikes pass with rail facing side forward into transfer courses. defined by head supporting spaced rails to allow the spike to remain in a vertical position and be slidably supported by the head until appropriately singulated and passed for ultimate dispersal in one of the prior art devices.

In providing such mechanism it is:

A principal purpose of my invention to provide a mechanism that positions rail spikes in a vertical attitude, with rail contacting head in predetermined orientation by gravity passage through aligning courses, without human intervention.

A further purpose to provide such a device that takes rail spikes from a random supply.

A still further object to provide such a device that is readily adapted for use as an auxiliary structure upon existing spike driving and aligning mechanisms.

A still further object to provide such a device that is of mechanically simple nature to give a highly reliable operation while yet being entirely automatic and operable without human attendance.

A still further object to provide such a device that is of new and novel nature, of simple economic design, of great and reliable use, and one otherwise well adapted for the uses for which it is intended.

Other and further objects of my invention will appear from the following specification and accompanying drawings which form a part of this application. In carrying out the objects of my invention, however, it is to be understood that its general features are susceptible of change in design and structural ar rangement, with only one preferred and practical embodiment being illustrated in the accompanying drawings as required.

BRIEF DESCRIPTION OF DRAWINGS In the accompanying drawings, wherein like numbers of reference refer to similar parts throughout:

FIG. 1 is an orthographic side view of my invention in place on a car supported by typical rail-bed structure.

FIG. 2 is an orthographic top view of the invention of FIG. I, showing the various parts, their relationship and configuration from this aspect.

FIG. 3 is a partial, isolated, top orthographic view of the driving mechanism of my invention, showing the various mechanical linkages.

FIG. 4 is an orthographic side view, somewhat enlarged, of a part of the driving mechanism of FIG. 3, taken on the line 3-3 thereon in the direction indicated by the arrows.

FIG. 5 is an orthographic top view of the input troughs and the upper part of the lateral alignment chutes.

FIG. 6 is a similar orthographic top view of the lower portion of the lateral alignment structure with the plane of the projection parallel to the rails, showing particularly the mounting of the forward part of this structure and the singulating devices associated therewith.

FIG. 7 is a partial, cutaway, orthographic side view of the lateral alignment course, showing its surface configuration.

FIG. 8 is a view of a railroad spike of the ordinary design.

FIG. 9 is an orthographic top view of the head aligning course, showing the alignment troughs and the various exit courses. I

FIG. is a vertical cross section view through one trough of FIG. 9, taken on the line 10-10 thereon in the direction indicated by the arrows.

DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings in more detail and particularly to those of FIGS. 1 and 2, it will there be seen that my invention generally comprises frame 11 supporting in its upper portion pickup structure 12 that moves spikes from a source of supply (not shown) to lateral aligning course 13 which in turn passes the spikes to lip aligning course 14 from whence the aligned spikes pass to transfer course 15 for ultimate disposal.

In these Figures there is seen an ordinary railroad car with frame 16 supported by wheels 17 on rails 18 carried by plural ties 19 supported on the earth 20. Plural spikes 21 communicate, either with or without tie plates, between rails 18 and ties 191 These spikes are shaped substantially as illustrated in FIG. 8 with elongate body 22, generally of rectangular cross section, terminating in lower point 23 at one end and head 24, having rail lip 25 extending as a protuberance in one direction, at the other end. The spike when driven must be positioned with the rail lip 25 facing the rail immediately adjacent the spike head, so that the rail lip extends over the lower flange of the rail to hold it in position. If tie plates be used on top of the tie to support the rail, the spike must be similarly positioned and pass through an appropriate hole in the tie plate. The object of my invention is to properly align this type of spike, which is almost universally used in present day railroad construction.

Principal frame 11, of a peripheral nature, comprises lower cross elements 26 communicating with the rail vehicle and with uprignts 27 which turn structurally communicating with various upper cross elements 28 to form a rigid structure capable ofsupporting the various elements of my invention.

Auxiliary frame 29 extends upwardly from cross element 28A to support the pickup structure. In the lateral portions of this auxiliary frame, brackets 30 extend upwardly to pivotably support elongate pickup arms 31 carrying in their rearwardmost extension closed circuit electromagnets 32 adapted to pick up one of a plurality of magnetically permeable rail spikes from a laterally disposed source of supply (not shown in the drawings for sake of clarity). Each pickup arm pivotably communicates, rearwardly of its pivot, by support 33 with pin 34 rotatably carried in the periphery of drive wheel 35. This drive wheel is activated by motor 36 and journaled on auxiliary frame 29 for rotary motion. With this structure then, as one pickup arm is at its later almost (outward) position, the other will be in its inwardmost position, so that each will pick up and deposit spikes alternately. The inwardmost position of the arms is regulated to be vertically above deposition chute 37 of side aligning course 13, so that when electromagnets 32 are deactivated at their innermost position the spike carried thereby will be deposited in the chute.

Lateral aligning course 13 includes deposition chute 37, of U"-shaped cross-sectional configuration, angled downwardly and forwardly to move spikes therein downwardly by gravity action aided by shaking motion to overcome static friction The chute is mounted in its rearwardmost portion upon depending bracket 38 rotatably carrying on each side vertically disposed, spaced rollers 39 communicating respectively on each side ofthe horizontal elements 40 ofbraeket 41, which in turn is supported by upper crossmember 28A. With this structure the chute is free to move in a forwardly-rearwardly directed course for some slight distance. Medially disposed, depending drive bracket 42 pivotably communicates with driving am 43 which in turn is carried by the external race of eccentric bearing 44, the internal race of which is carried by principal drive shaft 45. With this linkage, and upon rotation of principal drive shaft 45, a slight, cyclical, forward-rearward motion of the deposition chute will result to cause a forwardrcarward shaking action to aid in moving spikes carried in the chute therealong by overcoming the static friction between spikes and chute.

As seen particularly in FIG. 5, the lower medial portion of deposition chute 37 forms two spaced channels 46 of an open width adapted to accept the body of a rail spike in a sliding fit, so that the sides support the spike heads. Parallel spaced rails 47 communicate with channels 46 to form a continuous downwardly sloping course. In the lower medial part of this course, the spike channels split to the spaced parallel relationship illustrated in FIG. 6 to provide for the singulator. Rails 47 are preferably hollow tubes to aid in providing appropriate support. The lowermost portions of the rails are supported by smaller rods 48 that slidably fit within the internal channel of the rails. Rods 40 in turn communicate with supports 49 carried by tubular cross element 50 to allow some slight forwardrearward motion of the rails. The shaking motion of the deposition chute will be transmitted to the rails to aid in moving spikes by gravity downwardly therealong, when the spikes are supported on the rails by their heads.

Crosspiece 51 is provided immediately below the split rail courses in their lower medial portion to communicate between the two intermost rails. This crosspiece is journaled on vertical rod 51 extending angularly and downwardly therefrom to a conical-type pivotable support on bracket 52 supported by frame 11. As seen particularly in FIG. 6, the upper portion of rod 51 rotatably communicates with Y"- shaped yoke 53 irrotatably carrying vertically upwardly extending driving rod 54. This rod is vertically journaled upon auxiliary frame 29 and powered for rotation by motor 36. Cross element 50 is slidably carried for forward-rearward motion under the chute rails. At each side it pivotably carries paired opposed dogs 55 having triangular extensions 56 extending into the spike channel. These dogs are biased by springs 57 to the position shown, but moveable against the spring bias out of the spike channel. Similar paired-opposed dogs 58 are pivotably mounted on the outer rail structures at a spaced distance below dogs 55 and similarly biased by springs 57. With this structure then, cross element 50 will move forwardly and rearwardly upon motion of vertical rod 51 to cooperate with the two sets of dogs 55, 58 to singulate the passage of spikes along this course. Any surplus spikes may remain slidably supported in the channel above dogs 55.

With this arrangement of the lateral aligning channel, it is seen that spikes will be passed from the deposition chute into this channel to be there slidably supported by their heads upon the side rails. Since the spikes are not so wide in a lateral direction as through the rail lip, they will be oriented with the rail lip parallel to their course of travel and extending either forwardly or rearwardly therealong.

The forwardmost extension of rails 47 terminates in a downwardly and forwardly extending curve 60 so that spikes passing thereover will be properly oriented (with points forwardmost) in the lip aligning channel 14 therebelow.

Lower support rail 59 may be added under each channel rail, at a depth not quite so great as the length of a spike shank, to aid in maintaining the spikes in vertical orientation without too much lateral movement therefrom during their passage along the laterally lining course.

Lip aligning course 14 comprises spaced, parallel, U- shaped alignment troughs, supported in their forward portions by cross elements 63 and extending rearwardly and downwardly therefrom. The forward portion of each of these troughs in enlarged somewhat by upwardly extending side elements 62 to aid in maintaining transferring spikes within the troughs. Cross element 63 is supported as shown in FIG. 1 by L"-shaped brackets 64 structurally communicating with tubular element 65 pivotably carried upon rod 66 structurally carried by frame 11. The laterally projecting end part of crosspiece 63 communicates by pivotably movable linkage with drive rod 67 which in turn pivotably communicates with Y"- shaped yoke 68 carried by the outer race of eccentric bearing 69, the inner race of which is carried on principal drive shaft 45. It is to be noted that drive rod 67 communicates at an angle to both drive shaft 45 and cross element 63 so that both a lateral and a forward-rearward motion are transmitted to this element upon rotary motion of the drive shaft to cause a motion in the chutes wherein one particular point would cyclically travel in an elliptical course during chute motion. This type of motion is necessary to properly align spikes within the chutes.

The lowermost portion of each alignment trough communicates with paired opposed rails 70, again defining a channel wherein a spike is supported by its head with body depending downwardly in the channel therebetween. These rails are supported by the U-shaped brackets 71 which do not interfere with spike passage and the brackets in turn are supported by auxiliary frame structure 72 communicating with principal frame ll. Each channel preferably divides by means of Y" connections 73, having pivotably mounted alternating dogs 74 therein, as heretofore known in the art. From this point the spikes may move by gravity to plural disposition points as desired, according to methods hereto fore well-known. One particular form of spike driving device 75 is illustrated in FIGS. 1 and 2. Separate known means (not shown) must be provided to hold spikes during the start of the driving opera tion, but neither these nor the driving devices are part of my present invention per se and machines to accomplish these functions are known in the art.

The principal powering mechanism is seen in FIG. 3. Motor 76 communicates by linkage 77 with principal drive shaft 45 supported for rotation upon principal frame I]. The principal drive shaft carries eccentric linkage structure 44 to drive deposition chute 37. Auxiliary linkage 78 communicates from the principal drive shaft to lower auxiliary drive shaft 79, again journaled on frame 11. This shaft carries eccentric linkage 69 communicating with the lip aligning course structure as previ ously described. Preferably all the driving mechanism is electric for convenience and simplicity of control and operation.

Having thusly described the structure of my invention, its operation may now be understood.

Firstly, a mechanism is constructed according to the foregoing specification and a random supply of ferrous railroad spikes, of the ordinary design illustrated in FIG. 8, provided substantially on a horizontal plane laterally of the pickup structures 12.

My mechanism is activated. One pickup arm will alternately move pivotably outward immediately over the random supply of spikes (not shown) and the electromagnets carried thereby are activated by position sensitive switches to pick up a spike; thereafter, the arm moves back inwardly above disposition chute 37, at which point the electromagnet is inactivated by a position sensitive switch to drop the carried spike in the deposition chute. It is to be noted that since the electromagnets are of a closed circuit variety, each will pick up only one spike in one cycle to aid in spacing spikes during transit through my device. It is further to be noted that the mechanical linkage joining the pickup arms will cause each to operate alternately, directly out of phase with the other, so that one picks up a spike when the other deposits one.

Upon entry of spikes in the deposition chute, they will be jiggled in a forward-rearward direction by the particular mechanical linkage of the chute with the main drive shaft, and by reason of the slope of the chute this jiggling is such to overcome static friction between spike and chute to cause the spike to pass downwardly to the lower forward part of the chute. When the spike comes to this position the motion and configuration of the chute will ultimately cause the spike body to pass over and align substantially parallel to one of the channels 46, and when it does the spike body will move vertically downward so that the spike will then be slidably supported on the channel sides by its head with body depending in the channel. Since the spikes are thicker in their cross section in a forward-rearwarddirection, that is, parallel to the rail lip, the channel width is limited to substantially this distance so that a spike is oriented in the channel with the greater cross-sectional dimension extending parallel to the spike course of travel and with rail lip pointed either forwardly or rearwardly.

In this condition, and by reason of the slope of the spike channel and its jiggling motion, the spikes will be transferred down the channel to the singulating device. Here upon each cyclical motion of the singulating device, a spike will be passed down each channel. The timing of this operation may be appropriately predetermined to provide the ultimately desired supply of spikes.

The spikes continue downwardly past the singulator to the lower forward end of the lateral aligning course. Here the heads pass forwardly and downwardly so that as the spike enters the upper part of the lip aligning course, immediately below, the spike will be deposited point first with head facing rearward (with reference to spike course of travel).

At this point the mechanics of the spike must be understood to understand the function of the lip aligning course. The extension of the head of a spike away from its center of gravity is greatest in the direction of the'rail lip, so that if the spike be deposited with the rail lip down, the spike will have a higher potential energy than in other positions, in a narrowly curved U-shaped trough and with appropriate jiggling it will fall from this position into the lowest energy position with the back (side opposite the rail lip) of the spike facing downwardly in the chute. A spike in each position is illustrated in FIG. 10. With the motion of the lip aligning troughs then, as the spikes pass to the lower portion they will be aligned with rail lips facing upwardly, and as they exit from the lowermost portion of the lip aligning course to the rail defined transfer course, they will again be positioned vertically with the rail facing lip pointing forwardly by the same action as described for spike exit from the deposition trough.

The spikes then exit through any of the dispersal courses and are by them presented in appropriate position for further operation, with heads properly oriented. One particular form of dispersal course is illustrated in FIG. 2, though gravity transfer of positionally oriented spikes between two rails slidably supporting the heads may be accomplished in many other fashions.

It is to be remembered that the normal railroad spike has a rectangular cross section of body with a greater dimension in the direction parallel to the extension of the rail lips, though all spikes do not have this configuration and some may be square. My invention, however, will operate equally well upon a square spike, as the relatively small curvature of alignment troughs 61 of lip aligning course 14 will prevent a spike from passing down the course in a fashion with the rail lip in any position other than up.

It is further to be noted that my invention is an auxiliarytype structure that is well adapted for use with other devices known in the art to drive spikes, align them in proper position for driving, and hold them prior to driving.

The foregoing description of my invention is necessarily of a detailed nature so that a specific embodiment of it might be set forth as required, but is is to be understood that various modifications of detail, rearrangement and reordering of parts, and substitution of elements might be resorted to without departing from its spirit, essence or scope.

Having thusly described my invention, what I desire to protect by Letters Patent, and

Iclaim:

1. In an aligning device for rail spikes of the nature aforesaid the combination comprising:

a frame for support of:

a pickup structure carried in the upper portion of the frame having at least one pivotably mounted, laterally movable pickup arm carrying a closed circuit electromagnet, hav ing means of cyclically moving the arm between a medial and a lateral position to pick up spikes and means of activating the electromagnet when in a medial position to pick up and release a carried spike;

a lateral aligning course positioned below the medial position of the pickup arms to receive spikes therefrom, including a downwardly sloping trough terminating in its lower medial portion in two spaced channels of width great enough to allow passage of the body of the spike therethrough and small enough to support the head. with paired, spaced rails extending in a downward slope from each channel to terminate in a downwardly and forwardly extending curve to slidably support the head of a spike and allow spike passage therealong,

a lip aligning course immediately below the lowermost portion of the side aligning course including at least one relatively arcuate U-shaped trough, extending in a downward slope and direction opposite to that of the lateral aligning course, to receive spikes in a point forward fashion and turn them about their longer axis with rail lip extending upwardly; and means of transferring the aligned spikes from the lip aligning course in predetermined orientation.

2. The invention of claim 1 further characterized by the side aligning course being mounted for limited motion in a forward-rearward direction; and

mechanical linkage communicating with an eccentric bear ing carried by a rotatable shaft to cause cyclically reciprocating forward-rearward motion of the side aligning course.

3. The invention of claim 1 further characterized by the side aligning course being supported by a depending bracket with vertically spaced roller wheels on each side of the bracket to support it for linear motion relative to spaced opposed horizontal support members and carried by the frame communicating between each pair of roller wheelsv 4. The invention of claim 1 further characterized by the lip aligning course being movably mounted upon the frame with mechanical linkage associated with the lip aligning course to cyclically move this course so that a point thereon describes the periphery of a small ellipse during each motion cycle.

5. The invention ofclaim 1 further characterized by:

the lip aligning course being movably mounted upon the frame with associated mechanical linkage including a crosspiecc carried by the lip aligning course pivotably communicating with a lever extending at an angle to a yoke pivotably carried by the outer race of an eccentric bearing, the inner race of the bearing being irrotatably carried by a drive shaft extending substantially perpendicular to the lip aligning course to cause motion in the lip aligning course wherein one point thereon would describe a small ellipse during one motion cycle.

6. The invention of claim 5 wherein the crosspiece communicating with the lip aligning course is positioned in the upper portion of that course so that the upper portion of the course moves more than the lower portion.

7. The invention ofclaim 1 further characterized by a singulating device carried by the forward lower portion of the side aligning course, the singulating device including a transversely extending crosspiece carrying first opposed pivotably mounted dogs mechanically biased to a position extending into each spike channel, the crosspiece being mounted for slidable motion toward second similar cooperating dogs positioned at a spaced distance below the first dogs and means to cyclically move the crosspiece to pass a spike between each cooperating set of dogs upon each cyclical motion of the crosspiccei 

1. In an aligning device for rail spikes of the nature aforesaid the combination comprising: a frame for support of: a pickup structure carried in the upper portion of the frame having at least one pivotably mounted, laterally movable pickup arm carrying a closed circuit electromagnet, having means of cyclically moving the arm between a medial and a lateral position to pick up spikes and means of activating the electromagnet when in a medial position to pick up and release a carried spike; a lateral aligning course positioned below the medial position of the pickup arms to receive spikes therefrom, including a downwardly sloping trough terminating in its lower medial portion in two spaced channels of width great enough to allow passage of the body of the spike therethrough and small enough to support the head, with paired, spaced rails extending in a downward slope from each channel to terminate in a downwardly and forwardly extending curve to slidably support the head of a spike and allow spike passage therealong, a lip aligning course immediately below the lowermost portion of the side aligning course including at least one relatively arcuate ''''U''''-shaped trough, extending in a downward slope and direction opposite to that of the lateral aligning course, to receive spikes in a point forward fashion and turn them about their longer axis with rail lip extending upwardly; and means of transferring the aligned spikes from the lip aligning course in predetermined orientation.
 2. The invention of claim 1 further characterized by the side aligning course being mounted for limited motion in a forward-rearward direction; and mechanical linkage communicating with an eccentric bearing carried by a rotatable shaft to cause cyclically reciprocating forward-rearward motion of the side aligning course.
 3. The invention of claim 1 further characterized by the side aligning course being supported by a depending bracket with vertically spaced roller wheels on each side of the bracket to support it for linear motion relative to spaced opposed horizontal support members and carried by the frame communicating between each pair of roller wheels.
 4. The invention of claim 1 further characterized by the lip aligning course being movably mounted upon the frame with mechanical linkage associated with the lip aligning course to cyclically move this course so that a point thereon describes the periphery of a small ellipse during each motion cycle.
 5. The invention of claim 1 further characterized by: the lip aligning course being movably mounted upon the frame with associated mechanical linkage including a crosspiece carried by the lip aligning course pivotably communicating with a lever extending at an angle to a yoke pivotably carried by the outer race of an eccentric bearing, the inner race of the bearing being irrotatably carried by a drive shaft extending substantially perpendicular to the lip aligning course to cause motion in the lip aligning course wherein one point thereon would describe a small ellipse during one motion cycle.
 6. The invention of claim 5 wherein the crosspiece communicating with the lip aligning course is positioned in the upper portion of that course so that the upper portion of the course moves more than the lower portion.
 7. The invention of claiM 1 further characterized by a singulating device carried by the forward lower portion of the side aligning course, the singulating device including a transversely extending crosspiece carrying first opposed pivotably mounted dogs mechanically biased to a position extending into each spike channel, the crosspiece being mounted for slidable motion toward second similar cooperating dogs positioned at a spaced distance below the first dogs and means to cyclically move the crosspiece to pass a spike between each cooperating set of dogs upon each cyclical motion of the crosspiece. 